Low cost vehicle heat exchange devices manufactured from conductive loaded resin-based materials

ABSTRACT

Vehicle heat exchanger devices are formed of a conductive loaded resin-based material. The conductive loaded resin-based material comprises micron conductive powder(s), conductive fiber(s), or a combination of conductive powder and conductive fibers in a base resin host. The percentage by weight of the conductive powder(s), conductive fiber(s), or a combination thereof is between about 20% and 50% of the weight of the conductive loaded resin-based material. The micron conductive powders are metals or conductive non-metals or metal plated non-metals. The micron conductive fibers may be metal fiber or metal plated fiber. Further, the metal plated fiber may be formed by plating metal onto a metal fiber or by plating metal onto a non-metal fiber. Any platable fiber may be used as the core for a non-metal fiber. Superconductor metals may also be used as micron conductive fibers and/or as metal plating onto fibers in the present invention.

RELATED PATENT APPLICATIONS

This Patent Application is related to U.S. Patent ApplicationINT04-030B, Ser. No. ______, and filed on ______, which is hereinincorporated by reference in its entirety.

This Patent Application claims priority to the U.S. Provisional PatentApplication 60/578,415, filed on Jun. 9, 2004, which is hereinincorporated by reference in its entirety.

This Patent application is a Continuation-in-Part of INT01-002CIPC,filed as U.S. patent application Ser. No. 10/877,092, filed on Jun. 25,2004, which is a Continuation of INT01-002CIP, filed as U.S. patentapplication Ser. No. 10/309,429, filed on Dec. 4, 2002, now issued asU.S. Pat. No. 6,870,516, also incorporated by reference in its entirety,which is a Continuation-in-Part application of docket number INT01-002,filed as U.S. patent application Ser. No. 10/075,778, filed on Feb. 14,2002, now issued as U.S. Pat. No. 6,741,221, which claimed priority toU.S. Provisional Patent Applications Ser. No. 60/317,808, filed on Sep.7, 2001, Ser. No. 60/269,414, filed on Feb. 16, 2001, and Ser. No.60/268,822, filed on Feb. 15, 2001, all of which are incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

This invention relates to vehicle heat exchanger devices and, moreparticularly, to vehicle heat exchanger devices molded of conductiveloaded resin-based materials comprising micron conductive powders,micron conductive fibers, or a combination thereof, substantiallyhomogenized within a base resin when molded. This manufacturing processyields a conductive part or material usable within the EMF, thermal,acoustic, or electronic spectrum(s).

(2) Description of the Prior Art

Internal combustion engines generate a substantial amount of heat duringoperation. Therefore, vehicles powered by internal combustion enginesinclude a means for dissipating excess heat from the engine such thatthe engine is not damaged. Referring now to FIG. 1, a schematic of anexemplary vehicle engine cooling system 10 is illustrated. Two heatexchange devices, the radiator 12 and heater core 14, are depicted inthis schematic. The fan 16 is also indicated. A fan shroud, not shown,also is typical to an engine cooling system. In most modern engines,liquid coolant is circulated through the engine block 18, the enginecylinder head 20, and subsequently through the radiator 12 in order tocool the engine. When coolant temperature rises above a set temperature,the fan 16 engages to force additional airflow and thus additionalcooling across the radiator 12. The primary purpose of the heater core14 is to heat the vehicle passenger compartment on demand. The heatercore 14 is actually a heat exchange device which circulates enginecoolant in order to draw heat from the coolant much like the radiator12. Air is blown across the heater core 14 thus warming the air for usein the passenger compartment and cooling the engine coolant whichultimately cools the engine. Therefore, when the vehicle interior heateris in use, the heater core 14 acts as an additional heat exchange deviceto cool the engine. In the prior art, the heat exchange devices comprisemetals, such as aluminum or steel. These metals are effective asconductors of thermal energy but have several disadvantages includingcomplexity of manufacture, weight, and corrosion. A primary objective ofthe present invention is to provide vehicle heat exchange devices withreduced complexity of manufacture and reduced weight yet with improvedresistance to corrosion.

Several prior art inventions relate to vehicle heat exchange componentsand systems. U.S. Pat. No. 6,189,492 B1 to Brown teaches an automotivefan shroud that is integrally formed with liquid reservoirs made ofplastics resin. This invention also teaches the use of a reinforcedpolypropylene resin that is reinforced with approximately 40% talcumpowder to improve its strength and rigidity. U.S. Pat. No. 5,704,326 toMinegishi et al teaches an air induction system for an internalcombustion engine that utilizes air flow bodies and a collector bodyformed of a molded resin material. U.S. Patent Publication U.S.2004/0069446 A1 to Horiuchi teaches an integrated heat exchanger thatincorporates a radiator for use in engine cooling and a condenser foruse in the air-conditioning system that utilizes a resin tank betweenthe two structures. U.S. Pat. No. 5,220,809 to Voss teaches a coolingapparatus for an automotive air conditioning system electricalcontroller that incorporates the use of a chill block made of non-heatconductive plastic.

SUMMARY OF THE INVENTION

A principal object of the present invention is to provide an effectivevehicle heat exchange device.

A further object of the present invention is to provide a method to forma vehicle heat exchange device.

A further object of the present invention is to provide a vehicle heatexchange device that is lower in weight than prior art devices.

A further object of the present invention is to provide a vehicle heatexchange device that is easier to manufacture than prior art devices.

A further object of the present invention is to provide a vehicle heatexchange device that is will not corrode.

A further object of the present invention is to provide a vehicle heatexchange device molded of conductive loaded resin-based materials.

A yet further object of the present invention is to provide a vehicleheat exchange device molded of conductive loaded resin-based materialwhere the thermal or electrical characteristics can be altered or thevisual characteristics can be altered by forming a metal layer over theconductive loaded resin-based material.

A yet further object of the present invention is to provide methods tofabricate a vehicle heat exchange device from a conductive loadedresin-based material incorporating various forms of the material.

A yet further object of the present invention is to provide a method tofabricate a vehicle heat exchange device from a conductive loadedresin-based material where the material is in the form of a fabric.

In accordance with the objects of this invention, a vehicle heaterexchanger device is achieved. The device comprises a circulatory pipingand a plurality of fins attached to the circulatory piping. Thecirculatory piping comprises a conductive loaded, resin-based materialcomprising conductive materials in a base resin host.

Also in accordance with the objects of this invention, a vehicle heaterexchanger device is achieved. The device comprises a circulatory pipingand a plurality of fins attached to the circulatory piping. Thecirculatory piping comprises a conductive loaded, resin-based materialcomprising conductive materials in a base resin host. The percent byweight of the conductive materials is between about 20% and about 50% ofthe total weight of the conductive loaded resin-based material.

Also in accordance with the objects of this invention, a vehicle heaterexchanger device is achieved. The device comprises a circulatory pipingand a plurality of fins attached to the circulatory piping. Thecirculatory piping comprises a conductive loaded, resin-based materialcomprising micron conductive fiber in a base resin host. The percent byweight of the micron conductive fiber is between about 20% and about 50%of the total weight of the conductive loaded resin-based material.

Also in accordance with the objects of this invention, a method to forma vehicle heater exchanger device is achieved. The method comprisesproviding a conductive loaded, resin-based material comprisingconductive materials in a resin-based host. The conductive loaded,resin-based material is molded into a vehicle heater exchanger devicecomprising a circulatory piping; and a plurality of fins attached to thecirculatory piping. The circulatory piping comprises the conductiveloaded resin-based material.

Also in accordance with the objects of this invention, a method to forma vehicle heater exchanger is achieved. The method comprises providing aconductive loaded, resin-based material comprising conductive materialsin a resin-based host. The percent by weight of the conductive materialsis between 20% and 40% of the total weight of the conductive loadedresin-based material. The conductive loaded, resin-based material ismolded into a vehicle heater exchanger device comprising a circulatorypiping and a plurality of fins attached to the circulatory piping. Thecirculatory piping comprises the conductive loaded resin-based material.

Also in accordance with the objects of this invention, a method to forma vehicle heater exchanger is achieved. The method comprises providing aconductive loaded, resin-based material comprising micron conductivefiber in a resin-based host. The percent by weight of said micronconductive fiber is between 20% and 50% of the total weight of theconductive loaded resin-based material. The conductive loaded,resin-based material is molded into a vehicle heater exchanger devicecomprises a circulatory piping and a plurality of fins attached to thecirculatory piping. The circulatory piping comprises the conductiveloaded resin-based material.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings forming a material part of thisdescription, there is shown:

FIG. 1 illustrates an exemplary prior art vehicle engine cooling systemin schematic form.

FIG. 2 illustrates a first preferred embodiment of a conductive loadedresin-based material wherein the conductive materials comprise a powder.

FIG. 3 illustrates a second preferred embodiment of a conductive loadedresin-based material wherein the conductive materials comprise micronconductive fibers.

FIG. 4 illustrates a third preferred embodiment of a conductive loadedresin-based material wherein the conductive materials comprise bothconductive powder and micron conductive fibers.

FIGS. 5 a and 5 b illustrate a fourth preferred embodiment whereinconductive fabric-like materials are formed from the conductive loadedresin-based material.

FIGS. 6 a and 6 b illustrate, in simplified schematic form, an injectionmolding apparatus and an extrusion molding apparatus that may be used tomold vehicle heat exchanger devices of a conductive loaded resin-basedmaterial.

FIG. 7 illustrates a first preferred embodiment of the present inventionshowing a vehicle radiator comprising conductive loaded resin-basedmaterial.

FIG. 8 illustrates a second preferred embodiment of the presentinvention showing a vehicle heater core formed of conductive loadedresin-based material.

FIG. 9 illustrates a third preferred embodiment of the present inventionshowing a heat exchanger used in vehicle air conditioning systemscomprising conductive loaded resin-based material.

FIG. 10 illustrates a fourth preferred embodiment of the presentinvention showing vehicle hoses formed of conductive loaded resin-basedmaterial.

FIG. 11 illustrates a fifth preferred embodiment of the presentinvention showing a vehicle fan shroud formed of conductive loadedresin-based material.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention relates to vehicle heat exchanger devices molded ofconductive loaded resin-based materials comprising micron conductivepowders, micron conductive fibers, or a combination thereof,substantially homogenized within a base resin when molded.

The conductive loaded resin-based materials of the invention are baseresins loaded with conductive materials, which then makes any base resina conductor rather than an insulator. The resins provide the structuralintegrity to the molded part. The micron conductive fibers, micronconductive powders, or a combination thereof, are substantiallyhomogenized within the resin during the molding process, providing theelectrical continuity.

The conductive loaded resin-based materials can be molded, extruded orthe like to provide almost any desired shape or size. The moldedconductive loaded resin-based materials can also be cut, stamped, orvacuumed formed from an injection molded or extruded sheet or bar stock,over-molded, laminated, milled or the like to provide the desired shapeand size. The thermal or electrical conductivity characteristics ofvehicle heat exchanger devices fabricated using conductive loadedresin-based materials depend on the composition of the conductive loadedresin-based materials, of which the loading or doping parameters can beadjusted, to aid in achieving the desired structural, electrical orother physical characteristics of the material. The selected materialsused to fabricate the vehicle heat exchanger devices are substantiallyhomogenized together using molding techniques and or methods such asinjection molding, over-molding, insert molding, thermo-set, protrusion,extrusion, calendaring, or the like. Characteristics related to 2D, 3D,4D, and 5D designs, molding and electrical characteristics, include thephysical and electrical advantages that can be achieved during themolding process of the actual parts and the polymer physics associatedwithin the conductive networks within the molded part(s) or formedmaterial(s).

In the conductive loaded resin-based material, electrons travel frompoint to point when under stress, following the path of leastresistance. Most resin-based materials are insulators and represent ahigh resistance to electron passage. The doping of the conductiveloading into the resin-based material alters the inherent resistance ofthe polymers. At a threshold concentration of conductive loading, theresistance through the combined mass is lowered enough to allow electronmovement. Speed of electron movement depends on conductive loadingconcentration, that is, the separation between the conductive loadingparticles. Increasing conductive loading content reduces interparticleseparation distance, and, at a critical distance known as thepercolation point, resistance decreases dramatically and electrons moverapidly.

Resistivity is a material property that depends on the atomic bondingand on the microstructure of the material. The atomic microstructurematerial properties within the conductive loaded resin-based materialare altered when molded into a structure. A substantially homogenizedconductive microstructure of delocalized valance electrons is created.This microstructure provides sufficient charge carriers within themolded matrix structure. As a result, a low density, low resistivity,lightweight, durable, resin based polymer microstructure material isachieved. This material exhibits conductivity comparable to that ofhighly conductive metals such as silver, copper or aluminum, whilemaintaining the superior structural characteristics found in manyplastics and rubbers or other structural resin based materials.

The use of conductive loaded resin-based materials in the fabrication ofvehicle heat exchanger devices significantly lowers the cost ofmaterials and the design and manufacturing processes used to hold easeof close tolerances, by forming these materials into desired shapes andsizes. The devices can be manufactured into infinite shapes and sizesusing conventional forming methods such as injection molding,over-molding, or extrusion, calendaring, or the like. The conductiveloaded resin-based materials, when molded, typically but not exclusivelyproduce a desirable usable range of resistivity from between about 5 and25 ohms per square, but other resistivities can be achieved by varyingthe doping parameters and/or resin selection(s).

The conductive loaded resin-based materials comprise micron conductivepowders, micron conductive fibers, or any combination thereof, which aresubstantially homogenized together within the base resin, during themolding process, yielding an easy to produce low cost, electricallyconductive, close tolerance manufactured part or circuit. The resultingmolded article comprises a three dimensional, continuous network ofconductive loading and polymer matrix. Exemplary micron conductivepowders include carbons, graphites, amines or the like, and/or of metalpowders such as nickel, copper, silver, aluminum, or plated or the like.The use of carbons or other forms of powders such as graphite(s) etc.can create additional low level electron exchange and, when used incombination with micron conductive fibers, creates a micron fillerelement within the micron conductive network of fiber(s) producingfurther electrical conductivity as well as acting as a lubricant for themolding equipment. The addition of conductive powder to the micronconductive fiber loading may increase the surface conductivity of themolded part, particularly in areas where a skinning effect occurs duringmolding.

The micron conductive fibers may be metal fiber or metal plated fiber.Further, the metal plated fiber may be formed by plating metal onto ametal fiber or by plating metal onto a non-metal fiber. Exemplary metalfibers include, but are not limited to, stainless steel fiber, copperfiber, nickel fiber, silver fiber, aluminum fiber, or the like, orcombinations thereof. Exemplary metal plating materials include, but arenot limited to, copper, nickel, cobalt, silver, gold, palladium,platinum, ruthenium, and rhodium, and alloys of thereof. Any platablefiber may be used as the core for a non-metal fiber. Exemplary non-metalfibers include, but are not limited to, carbon, graphite, polyester,basalt, man-made and naturally-occurring materials, and the like. Inaddition, superconductor metals, such as titanium, nickel, niobium, andzirconium, and alloys of titanium, nickel, niobium, and zirconium mayalso be used as micron conductive fibers and/or as metal plating ontofibers in the present invention.

The structural material is a material such as any polymer resin.Structural material can be, here given as examples and not as anexhaustive list, polymer resins produced by GE PLASTICS, Pittsfield,Mass., a range of other plastics produced by GE PLASTICS, Pittsfield,Mass., a range of other plastics produced by other manufacturers,silicones produced by GE SILICONES, Waterford, N.Y., or other flexibleresin-based rubber compounds produced by other manufacturers.

The resin-based structural material loaded with micron conductivepowders, micron conductive fibers, or in combination thereof can bemolded, using conventional molding methods such as injection molding orover-molding, or extrusion, or calendaring, to create desired shapes andsizes. The molded conductive loaded resin-based materials can also bestamped, cut or milled as desired to form create the desired shape formfactor(s) of the vehicle heat exchanger devices. The doping compositionand directionality associated with the micron conductors within theloaded base resins can affect the electrical and structuralcharacteristics of the devices and can be precisely controlled by molddesigns, gating and or protrusion design(s) and or during the moldingprocess itself. In addition, the resin base can be selected to obtainthe desired thermal characteristics such as very high melting point orspecific thermal conductivity.

A resin-based sandwich laminate could also be fabricated with random orcontinuous webbed micron stainless steel fibers or other conductivefibers, forming a cloth like material. The webbed conductive fiber canbe laminated or the like to materials such as Teflon, Polyesters, or anyresin-based flexible or solid material(s), which when discretelydesigned in fiber content(s), orientation(s) and shape(s), will producea very highly conductive flexible cloth-like material. Such a cloth-likematerial could also be used in forming devices of rubber(s) orplastic(s). When using conductive fibers as a webbed conductor as partof a laminate or cloth-like material, the fibers may have diameters ofbetween about 3 and 12 microns, typically between about 8 and 12 micronsor in the range of about 10 microns, with length(s) that can be seamlessor overlapping.

The conductive loaded resin-based material of the present invention canbe made resistant to corrosion and/or metal electrolysis by selectingmicron conductive fiber and/or micron conductive powder and base resinthat are resistant to corrosion and/or metal electrolysis. For example,if a corrosion/electrolysis resistant base resin is combined withstainless steel fiber and carbon fiber/powder, then a corrosion and/ormetal electrolysis resistant conductive loaded resin-based material isachieved. Another additional and important feature of the presentinvention is that the conductive loaded resin-based material of thepresent invention may be made flame retardant. Selection of aflame-retardant (FR) base resin material allows the resulting product toexhibit flame retardant capability. This is especially important invehicle heat exchanger device applications as described herein.

The substantially homogeneous mixing of micron conductive fiber and/ormicron conductive powder and base resin described in the presentinvention may also be described as doping. That is, the substantiallyhomogeneous mixing converts the typically non-conductive base resinmaterial into a conductive material. This process is analogous to thedoping process whereby a semiconductor material, such as silicon, can beconverted into a conductive material through the introduction ofdonor/acceptor ions as is well known in the art of semiconductordevices. Therefore, the present invention uses the term doping to meanconverting a typically non-conductive base resin material into aconductive material through the substantially homogeneous mixing ofmicron conductive fiber and/or micron conductive powder into a baseresin.

As an additional and important feature of the present invention, themolded conductor loaded resin-based material exhibits excellent thermaldissipation characteristics. Therefore, vehicle heat exchanger devicesmanufactured from the molded conductor loaded resin-based material canprovide added thermal dissipation capabilities to the application. Forexample, heat can be dissipated from electrical devices physicallyand/or electrically connected to vehicle heat exchanger devices of thepresent invention.

As a significant advantage of the present invention, vehicle heatexchanger devices constructed of the conductive loaded resin-basedmaterial can be easily interfaced to an electrical circuit or grounded.In one embodiment, a wire can be attached to a conductive loadedresin-based device via a screw that is fastened to the device. Forexample, a simple sheet-metal type, self tapping screw, when fastened tothe material, can achieve excellent electrical connectivity via theconductive matrix of the conductive loaded resin-based material. Tofacilitate this approach a boss may be molded into the conductive loadedresin-based material to accommodate such a screw. Alternatively, if asolderable screw material, such as copper, is used, then a wire can besoldered to the screw that is embedded into the conductive loadedresin-based material. In another embodiment, the conductive loadedresin-based material is partly or completely plated with a metal layer.The metal layer forms excellent electrical conductivity with theconductive matrix. A connection of this metal layer to another circuitor to ground is then made. For example, if the metal layer issolderable, then a soldered connection may be made between the vehicleheat exchanger device and a grounding wire.

Where a metal layer is formed over the surface of the conductive loadedresin-based material, any of several techniques may be used to form thismetal layer. This metal layer may be used for visual enhancement of themolded conductive loaded resin-based material article or to otherwisealter performance properties. Well-known techniques, such as electrolessmetal plating, electro metal plating, metal vapor deposition, metallicpainting, or the like, may be applied to the formation of this metallayer. If metal plating is used, then the resin-based structuralmaterial of the conductive loaded, resin-based material is one that canbe metal plated. There are many of the polymer resins that can be platedwith metal layers. For example, GE Plastics, SUPEC, VALOX, ULTEM,CYCOLAC, UGIKRAL, STYRON, CYCOLOY are a few resin-based materials thatcan be metal plated. Electroless plating is typically a multiple-stagechemical process where, for example, a thin copper layer is firstdeposited to form a conductive layer. This conductive layer is then usedas an electrode for the subsequent plating of a thicker metal layer.

A typical metal deposition process for forming a metal layer onto theconductive loaded resin-based material is vacuum metallization. Vacuummetallization is the process where a metal layer, such as aluminum, isdeposited on the conductive loaded resin-based material inside a vacuumchamber. In a metallic painting process, metal particles, such assilver, copper, or nickel, or the like, are dispersed in an acrylic,vinyl, epoxy, or urethane binder. Most resin-based materials accept andhold paint well, and automatic spraying systems apply coating withconsistency. In addition, the excellent conductivity of the conductiveloaded resin-based material of the present invention facilitates the useof extremely efficient, electrostatic painting techniques.

The conductive loaded resin-based material can be contacted in any ofseveral ways. In one embodiment, a pin is embedded into the conductiveloaded resin-based material by insert molding, ultrasonic welding,pressing, or other means. A connection with a metal wire can easily bemade to this pin and results in excellent contact to the conductiveloaded resin-based material. In another embodiment, a hole is formed into the conductive loaded resin-based material either during the moldingprocess or by a subsequent process step such as drilling, punching, orthe like. A pin is then placed into the hole and is then ultrasonicallywelded to form a permanent mechanical and electrical contact. In yetanother embodiment, a pin or a wire is soldered to the conductive loadedresin-based material. In this case, a hole is formed in the conductiveloaded resin-based material either during the molding operation or bydrilling, stamping, punching, or the like. A solderable layer is thenformed in the hole. The solderable layer is preferably formed by metalplating. A conductor is placed into the hole and then mechanically andelectrically bonded by point, wave, or reflow soldering.

Another method to provide connectivity to the conductive loadedresin-based material is through the application of a solderable ink filmto the surface. One exemplary solderable ink is a combination of copperand solder particles in an epoxy resin binder. The resulting mixture isan active, screen-printable and dispensable material. During curing, thesolder reflows to coat and to connect the copper particles and tothereby form a cured surface that is directly solderable without theneed for additional plating or other processing steps. Any solderablematerial may then be mechanically and/or electrically attached, viasoldering, to the conductive loaded resin-based material at the locationof the applied solderable ink. Many other types of solderable inks canbe used to provide this solderable surface onto the conductive loadedresin-based material of the present invention. Another exemplaryembodiment of a solderable ink is a mixture of one or more metal powdersystems with a reactive organic medium. This type of ink material isconverted to solderable pure metal during a low temperature cure withoutany organic binders or alloying elements.

A ferromagnetic conductive loaded resin-based material may be formed ofthe present invention to create a magnetic or magnetizable form of thematerial. Ferromagnetic micron conductive fibers and/or ferromagneticconductive powders are mixed with the base resin. Ferrite materialsand/or rare earth magnetic materials are added as a conductive loadingto the base resin. With the substantially homogeneous mixing of theferromagnetic micron conductive fibers and/or micron conductive powders,the ferromagnetic conductive loaded resin-based material is able toproduce an excellent low cost, low weight magnetize-able item. Themagnets and magnetic devices of the present invention can be magnetizedduring or after the molding process. The magnetic strength of themagnets and magnetic devices can be varied by adjusting the amount offerromagnetic micron conductive fibers and/or ferromagnetic micronconductive powders that are incorporated with the base resin. Byincreasing the amount of the ferromagnetic doping, the strength of themagnet or magnetic devices is increased. The substantially homogenousmixing of the conductive fiber network allows for a substantial amountof fiber to be added to the base resin without causing the structuralintegrity of the item to decline. The ferromagnetic conductive loadedresin-based magnets display the excellent physical properties of thebase resin, including flexibility, moldability, strength, and resistanceto environmental corrosion, along with excellent magnetic ability. Inaddition, the unique ferromagnetic conductive loaded resin-basedmaterial facilitates formation of items that exhibit excellent thermaland electrical conductivity as well as magnetism.

A high aspect ratio magnet is easily achieved through the use offerromagnetic conductive micron fiber or through the combination offerromagnetic micron powder with conductive micron fiber. The use ofmicron conductive fiber allows for molding articles with a high aspectratio of conductive fiber to cross sectional area. If a ferromagneticmicron fiber is used, then this high aspect ratio translates into a highquality magnetic article. Alternatively, if a ferromagnetic micronpowder is combined with micron conductive fiber, then the magneticeffect of the powder is effectively spread throughout the molded articlevia the network of conductive fiber such that an effective high aspectratio molded magnetic article is achieved. The ferromagnetic conductiveloaded resin-based material may be magnetized, after molding, byexposing the molded article to a strong magnetic field. Alternatively, astrong magnetic field may be used to magnetize the ferromagneticconductive loaded resin-based material during the molding process.

The ferromagnetic conductive loading is in the form of fiber, powder, ora combination of fiber and powder. The micron conductive powder may bemetal fiber or metal plated fiber. If metal plated fiber is used, thenthe core fiber is a platable material and may be metal or non-metal.Exemplary ferromagnetic conductive fiber materials include ferrite, orceramic, materials as nickel zinc, manganese zinc, and combinations ofiron, boron, and strontium, and the like. In addition, rare earthelements, such as neodymium and samarium, typified byneodymium-iron-boron, samarium-cobalt, and the like, are usefulferromagnetic conductive fiber materials. Exemplary ferromagnetic micronpowder leached onto the conductive fibers include ferrite, or ceramic,materials as nickel zinc, manganese zinc, and combinations of iron,boron, and strontium, and the like. In addition, rare earth elements,such as neodymium and samarium, typified by neodymium-iron-boron,samarium-cobalt, and the like, are useful ferromagnetic conductivepowder materials. A ferromagnetic conductive loading may be combinedwith a non-ferromagnetic conductive loading to form a conductive loadedresin-based material that combines excellent conductive qualities withmagnetic capabilities.

Referring now to FIG. 7, a first preferred embodiment of the presentinvention is illustrated. A radiator 100 comprising conductive loadedresin-based material is shown. The radiator 100 construction includes aplurality of parallel tubes 130 which carry the engine coolant and aplurality of fins 132 which dissipate heat from the tubes as isconventional. The unique aspect of the present invention is the use ofconductive loaded resin-based material in this application. Onepreferred embodiment of the radiator 100 is to construct the entireradiator 112 including the tubes 130, fins 132, and the surroundingencasement 134 of conductive loaded resin-based material. In this case,the conductive loaded resin-based components of the radiator 112 areformed using molding techniques as described previously. The conductiveloaded resin-based material tubes 130 are, for example, extruded. Theconductive loaded resin-based material fins 132 are injection molded, oralternately stamped, and formed into fins 132 which provide a largeamount of surface area in a compact space. During the fabricationprocess, the fins 132 are joined to the tubes 130 in order to maximizeheat transfer between the tubes and fins. This joining process isaccomplished by over-molding or ultrasonic welding or by other meansknown to those skilled in the art. As an additional fabrication option,the fins 132 and tubes 130 are concurrently molded into a one-piecefin/tube unit. This unit is then attached to the conductive loadedresin-based material encasement 134 which contains a cavity for fluidpassage.

According to one embodiment, the radiator 100 utilizes conductive loadedresin-based material for all of the components as described above exceptthat the interfaces of the radiator 112 to one or more outsidecomponents are reinforced with metal. For example, the radiatorinterface to the radiator cap, not shown, is accomplished by adding ametal piece to the radiator encasement 134 to accommodate the subsequentengagement of the radiator cap, not shown. In another embodiment, metalfins, such as the aluminum fins which are often found in the prior art,are combined with conductive loaded resin-based material tubes 130. Thetubes 130 are molded onto the metal fins thus providing efficient heattransfer from the engine coolant running through the tubes 130 to theair moving past the fins. This fin/tube unit is then attached to theconductive loaded resin-based material encasement 134. As is common inthe automotive industry, the radiator 112 may also contain a separatefluid circuit for transmission oil coolant. Alternately, thetransmission oil is cooled in a separate radiator-type heat exchangeralso comprising conductive loaded resin-based material as a part of thepresent invention. The conductive loaded resin-based material of thepresent invention hereby provides a low cost radiator and/ortransmission oil cooler for which the economics of fabrication make itadvantageous for use in vehicles. Weight is a further advantage ofconductive loaded resin-based material heat exchange devices. The heatexchange devices of the present invention offer a significant weightsavings when compared to their metal counterparts commonly found in usetoday. This results in lower vehicle weight and consequently providesincreased fuel efficiency.

Referring now to FIGS. 8 and 9, second and third preferred embodimentsof the present invention are illustrated. A low cost heater core 140comprising conductive loaded resin-based material is shown in FIG. 8.The heater core 140 is used in vehicles to heat the passengercompartment on demand. A heat exchanger 150 for a vehicle airconditioning system is shown in FIG. 9. Both the heater core 140 andheat exchanger 150 are of similar construction and operating principlesto the radiator as discussed in FIG. 7. Each is constructed, in part orin whole, of conductive loaded resin-based material of the presentinvention.

Referring now to FIG. 10, a fourth preferred embodiment of the presentinvention is illustrated. Hoses 160 comprising conductive loadedresin-based material are shown. Hoses 160 carry liquid coolant or air asa part of the many heating and/or cooling applications within the modernvehicle. These conductive loaded resin-based material hoses 160 replaceother hoses, tubes, and duct-work typically constructed of plastics,rubber, metal, or a combination thereof. There are several advantages ofconductive loaded resin-based material in this application. These hoses160 offer a significant weight savings when compared to their metalcounterparts commonly used today. This results in lower vehicle weightand consequently provides increased fuel efficiency. An additionalbenefit is the relative ease and low cost of manufacture. Conductiveloaded resin-based material hoses 160 are formed by extrusion, injectionmolding, or other means. They are readily fabricated in almost anydesired shape and size befitting the particular application. Thisincludes, but is not limited to, round cross-section, rectangularcross-section, straight lengths of tubing, and tubing curved to fit aparticular space available in the vehicle. In certain applications,flexible tubing is beneficial to vehicle assembly and/or service.Conductive loaded resin-based material hoses 160 are made to remainflexible in vehicle applications where this is desired. Varying degreesof flexibility are achieved by varying the base resin material and thedoping composition and directionality associated with the micronconductors.

Referring now to FIG. 11, a fifth preferred embodiment of the presentinvention is illustrated. A vehicle fan shroud 180 comprising conductiveloaded resin-based material is shown. Such a fan shroud 180 is used tosurround the fan 184 which draws air across the radiator fins. Theconductive loaded resin-based material fan shroud 180 provides theadvantages of thermal dissipation and structural integrity when comparedto common plastic fan shrouds often found in the prior art. As anadditional design option, the fan blades 184 comprise conductive loadedresin-based material. The shroud 180 or the fan blades 184 are easilyformed by injection or blow molding the conductive loaded resin-basedmaterial.

As a further embodiment a metal layer may be formed overlying theconductive loaded resin-based material of any of the above-describedheat exchanger devices. In any vehicle heat exchange device, if a metallayer, not shown, is used, this metal layer may be formed by plating orby coating. If the method of formation is metal plating, then theresin-based structural material of the conductive loaded, resin-basedmaterial is one that can be metal plated. There are very many of thepolymer resins that can be plated with metal layers.

The conductive loaded resin-based material of the present inventiontypically comprises a micron powder(s) of conductor particles and/or incombination of micron fiber(s) substantially homogenized within a baseresin host. FIG. 2 shows cross section view of an example of conductorloaded resin-based material 32 having powder of conductor particles 34in a base resin host 30. In this example the diameter D of the conductorparticles 34 in the powder is between about 3 and 12 microns.

FIG. 3 shows a cross section view of an example of conductor loadedresin-based material 36 having conductor fibers 38 in a base resin host30. The conductor fibers 38 have a diameter of between about 3 and 12microns, typically in the range of 10 microns or between about 8 and 12microns, and a length of between about 2 and 14 millimeters. The micronconductive fibers 38 may be metal fiber or metal plated fiber. Further,the metal plated fiber may be formed by plating metal onto a metal fiberor by plating metal onto a non-metal fiber. Exemplary metal fibersinclude, but are not limited to, stainless steel fiber, copper fiber,nickel fiber, silver fiber, aluminum fiber, or the like, or combinationsthereof. Exemplary metal plating materials include, but are not limitedto, copper, nickel, cobalt, silver, gold, palladium, platinum,ruthenium, and rhodium, and alloys of thereof. Any platable fiber may beused as the core for a non-metal fiber. Exemplary non-metal fibersinclude, but are not limited to, carbon, graphite, polyester, basalt,man-made and naturally-occurring materials, and the like. In addition,superconductor metals, such as titanium, nickel, niobium, and zirconium,and alloys of titanium, nickel, niobium, and zirconium may also be usedas micron conductive fibers and/or as metal plating onto fibers in thepresent invention.

These conductor particles and/or fibers are substantially homogenizedwithin a base resin. As previously mentioned, the conductive loadedresin-based materials have a sheet resistance between about 5 and 25ohms per square, though other values can be achieved by varying thedoping parameters and/or resin selection. To realize this sheetresistance the weight of the conductor material comprises between about20% and about 50% of the total weight of the conductive loadedresin-based material. More preferably, the weight of the conductivematerial comprises between about 20% and about 40% of the total weightof the conductive loaded resin-based material. More preferably yet, theweight of the conductive material comprises between about 25% and about35% of the total weight of the conductive loaded resin-based material.Still more preferably yet, the weight of the conductive materialcomprises about 30% of the total weight of the conductive loadedresin-based material. Stainless Steel Fiber of 6-12 micron in diameterand lengths of 4-6 mm and comprising, by weight, about 30% of the totalweight of the conductive loaded resin-based material will produce a veryhighly conductive parameter, efficient within any spectrum, thermal,acoustic, or electronic frequency. Referring now to FIG. 4, anotherpreferred embodiment of the present invention is illustrated where theconductive materials comprise a combination of both conductive powders34 and micron conductive fibers 38 substantially homogenized togetherwithin the resin base 30 during a molding process.

Referring now to FIGS. 5 a and 5 b, a preferred composition of theconductive loaded, resin-based material is illustrated. The conductiveloaded resin-based material can be formed into fibers or textiles thatare then woven or webbed into a conductive fabric. The conductive loadedresin-based material is formed in strands that can be woven as shown.FIG. 5 a shows a conductive fabric 42 where the fibers are woventogether in a two-dimensional weave 46 and 50 of fibers or textiles.FIG. 5 b shows a conductive fabric 42′ where the fibers are formed in awebbed arrangement. In the webbed arrangement, one or more continuousstrands of the conductive fiber are nested in a random fashion. Theresulting conductive fabrics or textiles 42, see FIG. 5 a, and 42′, seeFIG. 5 b, can be made very thin, thick, rigid, flexible or in solidform(s).

Similarly, a conductive, but cloth-like, material can be formed usingwoven or webbed micron stainless steel fibers, or other micronconductive fibers. These woven or webbed conductive cloths could also besandwich laminated to one or more layers of materials such asPolyester(s), Teflon(s), Kevlar(s) or any other desired resin-basedmaterial(s). This conductive fabric may then be cut into desired shapesand sizes.

Vehicle heat exchanger devices formed from conductive loaded resin-basedmaterials can be formed or molded in a number of different waysincluding injection molding, extrusion, calendaring, or chemicallyinduced molding or forming. FIG. 6 a shows a simplified schematicdiagram of an injection mold showing a lower portion 54 and upperportion 58 of the mold 50. Conductive loaded blended resin-basedmaterial is injected into the mold cavity 64 through an injectionopening 60 and then the substantially homogenized conductive materialcures by thermal reaction. The upper portion 58 and lower portion 54 ofthe mold are then separated or parted and the vehicle heat exchangerdevices are removed.

FIG. 6 b shows a simplified schematic diagram of an extruder 70 forforming vehicle heat exchanger devices using extrusion. Conductiveloaded resin-based material(s) is placed in the hopper 80 of theextrusion unit 74. A piston, screw, press or other means 78 is then usedto force the thermally molten or a chemically induced curing conductiveloaded resin-based material through an extrusion opening 82 which shapesthe thermally molten curing or chemically induced cured conductiveloaded resin-based material to the desired shape. The conductive loadedresin-based material is then fully cured by chemical reaction or thermalreaction to a hardened or pliable state and is ready for use.Thermoplastic or thermosetting resin-based materials and associatedprocesses may be used in molding the conductive loaded resin-basedarticles of the present invention.

The advantages of the present invention may now be summarized. Effectivevehicle heat exchange devices are achieved. Methods to form vehicle heatexchange devices are also achieved. The vehicle heat exchange devicesare lower in weight and easier to manufacture than prior art devices.The vehicle heat exchange devices will not corrode. The thermal orelectrical characteristics of the devices can be altered or the visualcharacteristics can be altered by forming a metal layer over theconductive loaded resin-based material.

As shown in the preferred embodiments, the novel methods and devices ofthe present invention provide an effective and manufacturablealternative to the prior art.

While the invention has been particularly shown and described withreference to the preferred embodiments thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade without departing from the spirit and scope of the invention.

1. A vehicle heater exchanger device comprising: a circulatory piping;and a plurality of fins attached to said circulatory piping wherein saidcirculatory piping comprises a conductive loaded, resin-based materialcomprising conductive materials in a base resin host.
 2. The deviceaccording to claim 1 wherein the percent by weight of said conductivematerials is between about 20% and about 50% of the total weight of saidconductive loaded resin-based material.
 3. The device according to claim1 wherein said conductive materials comprise micron conductive fiber. 4.The device according to claim 2 wherein said conductive materialsfurther comprise conductive powder.
 5. The device according to claim 1wherein said conductive materials are metal.
 6. The device according toclaim 1 wherein said conductive materials are non-conductive materialswith metal plating.
 7. The device according to claim 1 wherein saidplurality of fins comprises said conductive loaded resin-based material.8. The device according to claim 1 wherein said conductive loadedresin-based material is further plated with a metal layer.
 9. The deviceaccording to claim 1 further comprising a frame supporting saidcirculatory piping wherein said frame comprises said conductive loadedresin-based material.
 10. A vehicle heater exchanger device comprising:a circulatory piping; and a plurality of fins attached to saidcirculatory piping wherein said circulatory piping comprises aconductive loaded, resin-based material comprising conductive materialsin a base resin host wherein the percent by weight of said conductivematerials is between about 20% and about 50% of the total weight of saidconductive loaded resin-based material.
 11. The device according toclaim 10 wherein said conductive materials are nickel plated carbonmicron fiber, stainless steel micron fiber, copper micron fiber, silvermicron fiber or combinations thereof.
 12. The device according to claim10 wherein said conductive materials comprise micron conductive fiberand conductive powder.
 13. The device according to claim 12 wherein saidconductive powder is nickel, copper, or silver.
 14. The device accordingto claim 12 wherein said conductive powder is a non-metallic materialwith a metal plating.
 15. The device according to claim 10 wherein saidplurality of fins comprises said conductive loaded resin-based material.16. The device according to claim 10 further comprising a framesupporting said circulatory piping wherein said frame comprises saidconductive loaded resin-based material.
 17. The device according toclaim 14 wherein said conductive loaded resin-based material furthercomprises a ferromagnetic material.
 18. A vehicle heater exchangerdevice comprising: a circulatory piping; and a plurality of finsattached to said circulatory piping wherein said circulatory pipingcomprises a conductive loaded, resin-based material comprising micronconductive fiber in a base resin host wherein the percent by weight ofsaid micron conductive fiber is between about 20% and about 50% of thetotal weight of said conductive loaded resin-based material.
 19. Thedevice according to claim 18 wherein said micron conductive fiber isstainless steel.
 20. The device according to claim 18 wherein saidmicron conductive fiber has a diameter of between about 3 μm and about12 μm and a length of between about 2 mm and about 14 mm.